I've had this XPS 13 9343 (upgraded to Windows 10) for only a month, and as far as I can remember this problem has always existed:
Two-finger scrolling on the touchpad does not work in MS Word 2013, either horizontally or vertically. Sometimes the window moves slightly as though the touchpad command is affecting the window rather than the text in it, although the window then springs back to its original position.
Touchpad scrolling works normally in all other programs (including other Office 2013 programs), whether or not Word is open.
A minor problem, but annoying. I've found some mentions online of other people having similar problems with Word 2013, but nothing specific to Dell and no clear solutions. Any ideas?